West Ham's manager Sam Allardyce pointed the finger at his debutant defender Callum McNaughton, who was sent off during his side's second-round defeat by Aldershot on Wednesday night, to explain the result. The Hammers had been booed off after letting in a late goal for the third match running at Upton Park, as Danny Hylton's goal ensured the League Two side reached the second round for the first time since they re-formed in 1992.

Allardyce, who says his players are scared of playing at home, made nine changes, including a debut for the 19-year-old centre-half McNaughton. And all looked well when Junior Stanislas fired West Ham into the lead with a superb curler after 16 minutes. But their night, and in particular McNaughton's, went sour as he was sent off for scything down Hylton a minute after half-time.

The defeat leaves Allardyce without a home win as the Hammers manager, but he said: "We didn't get our first win because we went down to 10 men, it's as simple as that. Even if the opposition are not in the same division, it gives them a massive lift. We were nice and comfortable but unfortunately a young man on his debut gets caught out and gets sent off.

"By the letter of the law, the referee has seen it as a goal-scoring opportunity – he's last defender so he [the referee] has to do what the rules tell him. In the end we tried to go for the win – I didn't want extra-time. It's not the same as 11 versus 11. I think we would have won the game."

Aldershot arrived in east London without a point or a goal from their previous three matches, so for West Ham fans there was almost an inevitability about the equaliser in the 78th minute, when stand-in Hammers keeper Ruud Boffin blocked Alex Rodman's shot and the rebound landed kindly for Luke Guttridge to tuck away.

And with a minute of time remaining, after a goalmouth scramble the ball fall to Hylton 18 yards out and he drove a low, angled shot past Ruud Boffin.

The result was sweet for Aldershot's manager, Dean Holdsworth, a self-confessed West Ham fan who played for Allardyce at Bolton. "I'm delighted for the players, for the fans and for the club," he said.

"West Ham put a strong side out and we gave a good account of ourselves. I think the world of Big Sam, but this is about my team tonight. It's the best feeling I've had since becoming a manager."